Composite evaporative cooler pads



April 8, 195% w. H. GOETTL 2,829,732

COMPOSITE EVAPORATIVE COOLER PADS Filed April 19, 1954 [L76 3 INVENTOR. WILLIAM H. GOEZ'TL 2,829,732 Patented Apr. 8, 1958 United. States Patent Ofiice W2,s29,"73z coMrosrrE EVAPORATWE COOLER PADS v William H.Goettl Phoenix, Arlz. ApplicationiApril 19,1954, swarm. 424,101 whims l- 13??? This invention pertains to composite: evaporating pads for evaporative air coolers. Y

Heretofore, pads for evaporative 'coolers have, for the most part, been made of porous fibrous; substances; such as, for example excelsior. This. substance is-comparatively cheap, and efiicient but the fibrous structure is so open that in many areas of the pads air is drawn into the cooler without adequate filtering, even when the pad is wet. Further, when the cooler is shut down and the pads allowed to dry, much dirt and dust is accumulated in the fibers which is drawn into the cooler and blown into the area being cooled when the cooler blower is started before the pads are fully wet.

At other times droplets of water are drawn through loose portions of the fibrous material and blown into the room being cooled.

Various means have been tried to overcome these objections. In some instances the excelsior was covered with cotton fabric, such as cheesecloth. But this quickly became covered with dust, dirt, dead insects and the like and interfered with the washing out of these substances that takes place in natural excelsior. It was also found that making the pads thicker thanapproximately two inches interferred with efiicient evaporation of the water passing downward through the pad and increased the resistance of the pad to the flow of air through it. In time the whole pad become fouled and had to be changed.

In view of the foregoing, one of the objects of my invention is to provide an evaporating pad for evaporative type air coolers which has a composite pad consisting of an outer layer of water absorbent fibrous wood excelsior, for efiicient evaporation, and an inner layer of non absorbent mineral wool, treated with an oily substance to render it water repellent;

A second object is to provide an evaporating pad for evaporative air coolers consisting of an outer layer of water absorptive fibrous material to evaporate water passing downward over this material, and an inner air filtering layer of finely spun fibrous inorganic substance, such as glass wool, treated with a heavy petroleum oil, to render it water repellent;

A third object contemplates the incorporation of a composite pad, as above described, in a frame adapted to fit into a pad opening in a cooler case, having a water supply trough at the top delivering Water to the top of the excelsior pad only, and lattice means for binding the two pads together and for securing the outer fibers of each pad portion in place.

I attain the foregoing objects by means of the structure, substances and combinations of parts illustrated in the accompanying drawings, in which- Figure 1 is a sectional elevation of a fragment of an evaporative cooler, showing my improved pad in position in one of the pad openings;

Figure 2 is an elevation of the back face of an edge portion of said pad; and

Figure 3 is an elevational view of the front face of an edge portion of said pad.

/5 is termed composite because it Similar numerals refer to similar parts in the several views.

In the drawings 2 indicates the air cooler case, 3 the blower within the case and 4 the opening in the case side ,which is closed by evaporating pad 5 in pad frame 6.

It will be noted that the pad frame 6 is closed on the outside by a louvered plate 7 and on the inside by a coarse screen 8. A water distributing trough 10 at the top of the frame 6 receives water from water supply pipe 12 and distributes it to the top of the outside portion, 15 of the pad 5 through openings 14 cut through the. front side 16 of the trough along its length.

The pad 5 is composite. The front portion 15 is composed of wood excelsior pressed into frame 6 while it. is held horizontally. After installation in frame 6 it receives water to be evaporated from trough 10. This water trickles downward through this portion of the pad, being absorbent into the fibers of the excelsior and producing refrigeration as air is drawn inwardly through the pad by blower 3. Excess water drains from the bottom of the pad into the sump 18 in the bottom of the cooler case 2 in the usual manner.

The back portion 20 of the pad 5 is composed of a flat pad of inorganic fibrous material such as matted finely drawn or spun glass fibers, or mineral wool, which is finely drawn fibers of slag folded in random fashion into a mat or pad. This pad, after being spread out on pad part 15, which is positioned horizontally during manufacture, is then treated by spraying with a non hardening heavy mineral oil, such as heavy thick refined petroleum. This oil sticks to the inorganic fibers of the .inner pad portion 26 and tends to make this pad portion water repellent. Unevaporated water particles from pad portion 15 are stopped by this pad portion and trickle down its front face along the area of contact 22 between the two pad portions. Dust, accumulated on the outer pad portions, when it is dry is caught by the treated fibers of the inner pad portion 20 and later washed down into the case sump, when the water flow becomes adequate.

If it is desired to run the cooler dry, the inner pad portion acts as a filler, and when the cooler is not used for a period of time dirt does not filter into the interior,

of the case.

From the foregoing it will be understood that the pad has outer and inner The fibrous wood excelsior 15 composing the front layer of the pad receives water from trough 1i and absorbs a portion of it and provides efficient evaporating surfaces for the production of refrigeration. 'The back portion or layer 20 of the pad acts as a dust and water filter. Since water is distributed to the front layer, only, the natural course of the water is downward through this front layer to the sump 18. However, air passing through the pad may draw droplets of water toward layer 20, but

since the material of this pad portion is water repellent,

no great amount of water enters this back layer and none passes through it. Any such unevaporated water droplets collect along the contact area 22 and follow this area to the bottom of the pad and then fall into the sump. No separation material between the two pad parts is necessary. The differences in the nature of the material provide suificient separation.

It is intended that substitutions for the exact materials specified shall be within the ambit of the invention, and that the arrangement of parts may be varied within the scope of the disclosure.

I claim: I

1. A composite evaporating pad for evaporative air coolers composed of an outer layer of wood excelsior and an inner layer of fibrous inorganic material treated with a heavy non-hardening oil to to entrap dust particles. 7

2. A pad for evaporative air coolers consisting of an outer layer of water absorbent fibrous Wood material producing refrigeration "by evaporation of WHICILBDG an inner filtering layer of non water absorbent inorganic said louvered plate and a back layer of fibrous inorganic material, between said front layer and said screen, treated with heavy non-hardening oil rendering it water repellent and resistant to the passage of dust particles; said water distribution trough supplying waterto said front layer of said pad only.

4. In an evaporative air cooler, having a case with a vertical outer wall provided with a rectangular opening for'the reception of an evaporating pad, and having a water supply system including a pipe having a discharge render it water repellent and opening at the top 'ofsaid rectangular-"opening: a' composite evaporatiye pad composed of a rectangular frame removably fitting into said rectangular opening of said case including a water distribution trough perforated on the bottom at the top of said frame, an outer face consisting of a louvered plate, and a coarse screen closing its inner face, a composite evaporative pad having an outer portion of excelsior positioned adjacent said louvered plate and inner portion coniposed of inorganic woollike fibers coated with non-hardening oil held'between said excelsior pad and said coarse screen; said excelsior pad being disposed so that itstop edge is below the perforations in the bottomfof-"said water distribution trough.

References" Cited in the file of this patent UNITED STATES PATENTS 2,608,396 Shapiro Aug. 26, 1952 

